After setting up your environment you can use regular rspec to
run tests:

bundle exec rspec
bundle exec rspec spec/apps/ruby_spec.rb

Tip: If you do not want to set VCAP_BVT_USER and VCAP_BVT_USER_PASSWD
you can run rake prepare (task used with parallel set up) once
and after that tests will just use first parallel user. (You will have
to set the VCAP_BVT_ADMIN_USER and VCAP_BVT_ADMIN_USER_PASSWD for this.
See below.)